Life on Venus
December 17, 2020
Like Mars, Venus is a planet that, scientists speculate, may contain life. In recent research led by Jane Greaves of Cardiff University, conducted using the James Clerk Maxwell Telescope (JCMT) in Hawaii and the Atacama Large Millimeter Array (ALMA) observatory in Chile, astronomers have observed phosphine gas, a possible indicator of life, in the clouds of Venus. According to MIT News, “if this stinky, poisonous gas were ever detected on a rocky, terrestrial planet, it could only be produced by a living organism there.” The potential for life on Venus is not too inconceivable, since in the atmosphere 48 to 60 kilometers above the planet’s surface, temperatures could permit the survival of some life forms, including extremophiles. In addition, the amino acid glycine, another potential hallmark of life, has been detected in Venus’s atmosphere. Scientists from Cardiff University, MIT, the University of Manchester, Cambridge University, MRC Laboratory of Molecular Biology, Kyoto Sangyo University, Imperial College, the Royal Observatory Greenwich, the Open University, and the East Asian Observatory collaborated to publish the discovery and analysis of the phosphine findings in the Nature Astronomy journal on September 14, 2020.
On October 26, a Nature Astronomy article by researchers at NASA Goddard was published in response to the September publication. It asserted that the traces interpreted to be phosphine were too similar to sulfur dioxide, a normal component of Venus’s atmosphere, to be reliably considered potential biomarkers. On November 17, the journal Astronomy & Astrophysics published another study conducted by Leiden University with similar claims.
Nevertheless, the September study has also been supported by other scientists. Biochemist Rakesh Mogul and his colleagues at Cal Poly Pomona re-analyzed the findings from NASA’s Pioneer Venus mission in 1978 to determine evidence of phosphorus in Venus’s atmosphere. This could indicate the presence of phosphine or other compounds, but Mogul claims that phosphine is most likely.
In response to skeptics, Greaves’s team reanalyzed its data and confirmed the presence of phosphine in Venus’s cloud deck. However, the team found the atmospheric concentration of the gas to average around 1 part per billion, a quantity 1/7 the size of its original approximation.
Now that phosphine on Venus is confirmed, the question of how, specifically, it was produced. Phosphine is involved in Earth’s cycling of phosphorus through the planet’s rocks, plants, soil, and water. However, scientists currently have no knowledge of such a biochemical exchange on Venus.
Whether phosphine does or does not indicate life on Venus is still a looming question that occupies many, but additional research may ultimately point to an answer. Scientists continue to investigate while many await the results. Perhaps this exploration will inspire others to become scientists themselves and be the ones interpreting and collecting the data.